AVIAN INFLUENZA (AI) BIRD FLU Czech University of Life Sciences Česká Zemědlská Univerzita v Praze Institute of Tropics and Subtropics MVDr.Joseh Holejšovský PhD (former General Director of SVA and Chief Veterinary Officer of the C R

Viral Classification Family: Orthomyxoviridae Genus: Influenza Virions (virus particles) are 80 to 120 nm in diameter May be filamentous  Influenza A virus causes human, swine, equine, avian, and marine mammal influenza and is the type associated with pandemic disease in humans.

THEORETICAL KNOWLEDGE 1.VIROLOGY 2.EPIZOOTHOLOGY 3.CLINICAL SIGNS 4.GROSS LESIONS

For influenza A viruses, there are 16 different HA antigens (H1 to H16) and 9 different NA antigens (N1 to N9). Only subtypes H5 and H7 of influenza A virus recently defined as highly pathogenic AI (HPAI) that have caused AI in poultry. The virus envelope has spike like projections of glyco-proteins, which have hemagglutinin (HA) and neuraminidase (NA) activity; these characteristics are used to subtype the A, B, and C viruses. Subtype A is most important virus causing serious outbreaks.

Avian Influenza (AI) can be divided into Highly Pathogenic Avian Influenza (HPAI) and Low Pathogenic Avian Influenza (LPAI). Highly pathogenic H5 and H7 virus causes HPAI. HPAI is one of the List A animal diseases both for World Organisation for Animal Health (OIE) but not LPAI. ● HPAI causes very high mortality in chicken, but not LPAI. ● Waterfowl plays very important role of reservoir. Persisting LPAI virus in chicken population might change its pathogenicity and become HPAI virus. No evidence showing that LPAI H5N2 virus can infect humans.

Low Pathogen AI Mild or no clinical signs in poultry Decreased egg production Mild respiratory signs: cough, sneeze Feces, ocular, oral and nasal secretions Bird-to-bird or contaminated equipment Diagnosis: –Virus isolation –Serology Source: AVIAN INFLUENZA / “BIRD FLU”,

Avian Influenza Numerous subtypes HxNx: 16 Hs and 9 Ns –Theoretically 144 combinations –Antigens on the virus surface Few have human health impact –H5N1, H7N2, H7N3, H7N7, H9N2 –Most no more than conjunctivitis

Distribution of subtypes HA a NA by species HA Human H1,H2, H3, (H5, H7, H9) Pig H1, H3 Horse H3, H7, tuleň H4 Birds 1-16 NA Human N1, N2, N8 pig N1, N2 Horse N7, N8, tuleň N7 Birds N1-9

Migrační cesty

Water fowls and migratory birds are the most potential agents to transmit the virus. These birds do not get infected but they are healthy carriers and shed virus through their feces (droppings) and other body secretions.

Influenza: Seasonal, HPAI, Pandemic Seasonal Influenza Highly PathogenicPandemic Influenza Avian Influenza Exposure from persons infectedinfected birds from persons infected with the usual circulating with a new virus subtype subtype, strains may vary Clinical fever, respiratory signs sustained fever >380C fever, respiratory signs, Manifestatio ns and symptoms that may shortness of breath severity to be determined or may not progress dry, non- productive cough, severe illness

Influenza: Seasonal, HPAI, Pandemic Seasonal InfluenzaHighly PathogenicPandemic Influenza Avian Influenza Etiology Influenza A (H3N2, H1N1) Pathogenic to humans:A new subtype Influenza BH5N1, H7N7 mutated H5N1 capable of human- to -human transmission Incubation Period2 to 3 days3 days? (range 1 to 7 days)(range 2 to 4 days)

Seasonal InfluenzaHighly PathogenicPandemic Influenza Avian Influenza Who are at risk young children, personschildren and adultsuncertain, of complications>50 y/o, persons with1918 pandemic- young, co-morbidities e.g DM,otherwise healthy, heart, lung, kidneyworking population disease,were affected immunocompromised Vaccineyearly vaccine strainsnone Treatmentsupportive, antiviral antiviral agent, if the agent within theagent within the 1stnew subtype is not 1st 2 days2 days, but shows resistant resistance in some Influenza: Seasonal, HPAI, Pandemic

Human Public Health Implications High mortality of H5N1 to humans Emergence of a new influenza virus with pandemic potential -Efficient human to human transmission -Vast majority of people have no immunity -No protective vaccine/ Inadequate quantity of developed vaccines for the world -High number of cases and deaths worldwide (pandemic)

Transmission to humans Close contact with infected birds and through aerosols, discharges and surfaces Virus is excreted in feces, which dries, pulverized and inhaled Flapping of wings hasten transmission

Stages of Avian and Pandemic Preparedness Stage 1: Avian influenza-free country Stage 2: Avian influenza in domestic fowl Stage 3: Avian influenza from poultry to humans Stage 4 - Human-to-human transmission (pandemic influenza) in the country

Stage 1: Keeping Country Bird Flu Free Prevention of entry of the virus: Ban of all poultry and poultry products from AI- infected countries Border control Ban on sale, keeping in captivity of wild birds Biosecurity measures Standardized footbath Confiscation and destruction of unlicensed cargo Surveillance of Poultry in Critical Areas Influenza vaccination for all poultry workers, handlers

STAGE 2: Avian Influenza in Domestic Fowl Individuals at risk  Poultry handlers/workers  Sellers/ people in live chicken sale  Aviary workers/ Ornithologists  Cullers  People living near poultry farms  Any individual in close contact with infected birds

STAGE 2: Avian Influenza in Domestic Fowl Prevention of spread from birds-to birds: early recognition and reporting, mass culling, quarantine of affected area Prevention of spread from birds to humans: human protection through proper handling of infected birds, use of protective gear by residents, poultry handlers, and response teams

STAGE 2: Avian Influenza in Domestic Fowl Response to sick or dead birds Protection of exposed residents – gloves/ plastic material in handling sick or dead birds, hand washing Personal protective equipment for cullers – caps, masks, goggles, gowns Identification of exposed individuals and quarantine for 7 days Reporting to the Health Emergency Response Team/ local health officer

STAGE 3- Avian Influenza in Humans Community response Patient: face mask, in a separate area or at least 1 meter distance from other people Monitoring of contacts of the case Protection of caregiver : face mask and goggles or eye glasses, hand washing, self- monitoring for signs and symptoms Immediate transfer to the Referral Hospital Protection of the transporting team and disinfection of vehicle

Import ban Border control Wildlife Act Early recognition/ reporting Mass culling, Quarantine of affected area Management of public panic Early recognition/ reporting Proper handling of birds Protective gear Management of public panic Use of antiviral agents Infection control Quarantine of contacts Passenger entry-exit management Border control Quarantine of contacts Isolation Management of cases Social distancing Personal hygiene Management of public panic Strategic Approaches

HOGS HOG MANURE This is an example of a duck farm outside of North America. Notice that the ducks are being raised outside. This means that they are free to comingle with migratory birds. This poses a huge biosecurity risk. Also, The barn in the picture is full of hogs. The manure from the hogs is running out to where the ducks are living. This poses a risk as the hogs, biologically, serve as a mixing vessel for disease organisms, which makes genetic mutation much easier, ultimately contributing to the risk of a human pandemic.

Keep Your Distance Restrict access to your birds –Gates, fences, locks No unnecessary visitors on your farm Keep your birds separated from wild game birds or migratory waterfowl

HPAI: Clinical Signs Incubation Period 3-7 days Clinical signs Sudden death without signs Lack of energy, appetite Severe depression with ruffled feathersLoss of appetite ( reduced feed consumption) Severe drop in egg production Edema of head and neck Swollen and cyanotic combs and wattles Discolored purple wattles, comb, legs Petechial hemorrhages on internal membrane surfaces Watery diarrhea that begins as bright green and progresses to white Diffuse hemorrhage between hocks and feet Nasal and ocular discharge Coughing/sneezing In-coordination and nervous signs

Know the Warning Signs of Infectious Bird Diseases Sudden increase in bird deaths in your flock. Sneezing, gasping for air, coughing, and. nasal discharge Watery and green diarrhea. Lack of energy and poor appetite.

Know the Warning Signs of Infectious Bird Diseases Drop in egg production or soft- or thin-shelled, misshapen eggs. Swelling around the eyes, neck, and head. Purple discoloration of the wattles, combs, and legs (AI).

Know the Warning Signs of Infectious Bird Diseases Tremors, drooping wings, circling, twisting of the head and neck, or lack of movement (END). Early detection is important to prevent the spread of disease.

Respiratory Diseases and HPAI There are many causes and is very common Signs: Coughing Sneezing Discharge from the eyes and nostrils

High Path AI Sudden death without clinical signs Source: AVIAN INFLUENZA / “BIRD FLU”,

Depression and gasping were found in the six-week-old native chickens.

High Path AI Decreased activity and decreased feed consumption F.A.O.- Italy Source: AVIAN INFLUENZA / “BIRD FLU”,

High Path AI Nasal discharge, coughing, sneezing Lack of coordination Diarrhea F.A.O.- Italy Source: AVIAN INFLUENZA / “BIRD FLU”,

Report Sick Birds

High Path AI Decreased egg production Soft-shelled or misshapen eggs Source: AVIAN INFLUENZA / “BIRD FLU”,

High Path AI Swelling of head, eyelids, comb, wattles and hocks Source: AVIAN INFLUENZA / “BIRD FLU”,

Gross Lesions HPAI Vesicles and ulcers on comb Facial edema Source: AVIAN INFLUENZA / “BIRD FLU”,

Gross Lesions HPAI Hemorrhage throughout internal body organs and fat Source: AVIAN INFLUENZA / “BIRD FLU”,

OIE, FAO

Gross Lesions HPAI Hemorrhage throughout internal body organs and fat Source: AVIAN INFLUENZA / “BIRD FLU”,

Avian Influenza Highly transmissible viral disease Infects a wide variety of wild and domestic birds Worldwide distribution 16 hemagglutinin and 9 neuraminidase subtypes Clinical signs and lesions variable

Economic Impact of AI Mortality Depopulation and disposal Lost production Cleaning and disinfection Interstate movement restrictions Trade restrictions